Another reason is market fluctuations.

That doesn't take into account market fluctuations as you mentioned so im hoping (at the very least) the market and I can meet somewhere in the middle.

My credit fluctuates between 725 - 745.

Discount is nice but can fluctuate wildly based on the loan rate, terms and more.To answer your question you can definitely invest in discounted notes to hedge your losses in a downturn.

I’d heard Riverside was growing but that the housing market there can fluctuate dangerously.

Toni, you'll see the price fluctuate.

They usually can not get credit or bank loans because of their fluctuating income.

While I understand that many of these experts have perpetually pessimistic views on society and the economy, it is undeniable that the market has been booming at the highest rate since the years leading up to the previous financial crisis.I understand from ample research on BP that many investment strategies are relatively unaffected by market dips and fluctuations because they are not typically reliant upon appreciation.

Also, the rules of thumbs would fluctuate. 

You should start to see patterns and a range--A location sales selling well over 10x GRM and B- sales selling in the 7 to 8 range (this will fluctuate).